The main objective of the Harvard Study of Adult Development is to understand successful aging. The project will continue a life course study of three socially contrasting cohorts totaling 724 men and 100 women who have been prospectively followed by interdisciplinary study for 55 years [Attrition has been held to 0.2 percent/year]: A. The COLLEGE sample includes 268 men selected as sophomores in 1939 1942 for mental and physical health and high achievement. At an average age of 75, these men are demonstrating marked longevity. B. The CORE CITY sample includes 456 men selected in 1940-44, at age II-IS, by the Gluecks as non-delinquent controls for their study of delinquency. They were from inner-city schools in high-crime neighborhoods. C. A sample of 100 women selected in 1920 from the Terman Study of Gifted Children are included as a comparison group. Major objectives over the period 1997-2002 will be to determine: l. What familial, childhood, and premorbid psychological variables (e.g. Major Depressive Disorder) are associated with deterioration of physical health, early retirement, and functional disability? How are these effects mediated? How do predictors change from decade to decade? 2. What is the natural history of marital and occupational careers over the adult life span? How do these careers relate to psychopathology and rate of age-related decline in health? 3. By what mediating processes have some men remained vigorous, engaged octogenarians? By what mediating processes have some socially disadvantaged men, whose mental health when young was poor, become competent septuagenarians? What are the predictors of "active" (disability free) life expectancy? Methodology over the 5-year period, 1997- 2002: The Study will continue to exploit the power of a multivariate, interdisciplinary and prospective design. Major variables are assessed by independent raters, kept blind to other data, using operationalized definitions. l. Contact will be maintained with the entire sample by means of biennial questionnaires and, when necessary, by telephone interviews. Health habits, marital, social, and work adjustment, as well as, leisure activities will be monitored. 2. Half of the COLLEGE sample are re- interviewed after retirement. 3. Physical exams are obtained on all subjects every 5 years and Instrumental Activities of Daily Living every 2 years. Telephone cognitive status exams will be obtained every 5 years.